1. Field of the Invention
This invention relates to ink jet printing and more particularly, to a nozzle for an ink jet printer.
2. Description of the Prior Art
In ink jet printers a nozzle is connected to a reservoir or other supply of liquid ink which is maintained under constant pressure. This causes ink to be discharged from an orifice in the nozzle in a continuous stream. The nozzle is vibrated in a manner which causes perturbations to be formed in the stream to cause it to break up into individual drops a relatively short distance from the nozzle. The vibrating mechanism may be either a piezoelectric or a magnetostrictive device.
It is known that the vibration of the nozzle by the transducer causes soundwaves to be propagated to the liquid mass of the ink within the nozzle. The resonances of the soundwaves in the liquid have an undesirable effect on the formation of drops. In U.S. Pat. No. 3,683,396, issued to R. I. Keur et al on Aug. 8, 1972, the nozzle structure is designed so that the fluid resonance is obtained. This requires that the design reconcile the mechanical resonance with the fluid resonance. Attention to the property of fluid resonance imposes strict limitation on the selection of the ink parameters which, if variable, affect the operation of such a device.